New module which shortens the URLs in the channel

Bitly module aims to shorten the URLs that are sent to the channel.

You might have experienced some troubles if you are using weechat and urxvt. Having the nicknames buffer next to the channel room, the long urls get broken if they are on several lines.
Thanks to bitly, you can configure this module in order to shorten the URLs that are not inline.

Bitly module use the bitly API python library which you can find here: <https://github.com/bitly/bitly-api-python/>

Maybe this module only concern a few people, but it helped me alot and still does. I let you decide if it worths being merged.